1. Field of the Invention
The present invention generally relates to nozzles and, more particularly, to reversible nozzles used in steam turbines.
2. Brief Description of the Prior Art
Nozzles are used in a variety of applications, one of which is directing steam in steam turbines. Steam turbines utilize nozzles to direct high pressure steam or gas toward turbine blades. For example, turbine nozzles are discussed in U.S. Pat. Nos. 1,750,652; 4,066,381; 4,097,188; 5,259,727; and 5,392,513. The high pressure gas exits the nozzles at high velocities and contacts the turbine blades causing the blades to rotate. The nozzles are typically installed in two ways. In one arrangement, a plurality of nozzles is assembled into a nozzle plate or ring and bolted into the turbine. Another arrangement involves drilling the turbine casing and then positioning and welding the nozzles into place.
From time to time, installed nozzles wear and must be removed and replaced. Further, depending on the turbine design, differently oriented nozzles are used to cause the turbine blades to rotate in either a clockwise direction or a counterclockwise direction. If the direction of rotation is to be changed, the nozzle must be removed and realigned. These are all time-consuming and expensive endeavors, especially if the nozzles are welded in place.
Therefore, it is an object of the present invention to provide nozzles which can be installed, removed, or reversed without welding.
The present invention generally relates to reversible nozzles removably connected to a fluid emitting base, with each nozzle having a nozzle tube and a nozzle body. Each nozzle tube defines a fluid inlet, a fluid exit aperture, and a nozzle passageway connecting the fluid inlet and the exit aperture. Each nozzle body is connected to a first end of a corresponding nozzle tube with each nozzle body forming an internal cavity and a plurality of fastener receiving slots. The nozzle tube extends along a nozzle axis, wherein the nozzle axis intersects a nozzle body axis, forming a nozzle angle between the axes.
In operation, the nozzle body and accompanying nozzle tube are positioned adjacent to a fluid emitting base, preferably with the nozzle tube projecting away from the fluid emitting base. Fluid exiting the fluid emitting base is received through the nozzle body cavity, enters the fluid inlet of the nozzle tube, moves through the nozzle passageway formed by the nozzle tube, and exits through the fluid exit aperture of the nozzle tube.
Each nozzle tube can direct fluid in a plurality of directions. In general, the direction of fluid exiting the fluid exit aperture of each nozzle tube is reversed from a first direction to a second direction by removing fasteners that removably connect each nozzle body and corresponding nozzle tube to the fluid emitting base, reversing the fluid exit aperture of each nozzle tube from a first direction to a second direction by rotating the nozzle body with respect to the fluid emitting base, aligning fastener receiving slots formed by each nozzle body with fastener receiving holes formed by the fluid emitting base, and reinstalling the fasteners through the fastener receiving slots formed by the nozzle body and the fastener receiving holes formed by the fluid emitting base. Removal of the nozzles for maintenance or replacement in similar, except that once the fasteners are removed, the old nozzle is removed, and the new nozzle is installed as indicated above.
These and other advantages of the present invention will be clarified in the Detailed Description of the Preferred Embodiments taken together with the attached drawings in which like reference numerals represent like elements throughout.